Cost-Related Medication Nonadherence Among Older Adults

Findings From a Nationally Representative Sample

Green C. Chung, MD; Richard A. Marottoli, MD, MPH; Leo M. Cooney, Jr, MD; Taeho Greg Rhee, PhD, MSW


J Am Geriatr Soc. 2019;67(12):2463-2473. 

In This Article

Abstract and Introduction


Objectives: To estimate the rate of and risk factors associated with cost-related medication nonadherence among older adults.

Design: Cross-sectional analysis of the 2017 National Health Interview Survey (NHIS).

Setting: Nationally representative health interview survey in the United States.

Participants: Survey respondents, aged 65 years or older (n = 5701 unweighted) in the 2017 wave of the NHIS.

Measurements: Self-reported, cost-related medication nonadherence (due to cost: skip dose, reduce dose, or delay or not fill a prescription) and actions taken due to cost-related medication nonadherence (ask for lower-cost prescription, use alternative therapy, or buy medications from another country) were quantified. We used a series of multivariable logistic regression analyses to identify factors associated with cost-related medication nonadherence. We also reported analyses by chronic disease subgroups.

Results: In 2017, 408 (6.8%) of 5901 older adults, representative of 2.7 million older adults nationally, reported cost-related medication nonadherence. Among those with cost-related medication nonadherence, 44.2% asked a physician for lower-cost medications, 11.5% used alternative therapies, and 5.3% bought prescription drugs outside the United States to save money. Correlates independently associated with a higher likelihood of cost-related medication nonadherence included: younger age, female sex, lower socioeconomic levels (eg, low income and uninsured), mental distress, functional limitations, multimorbidities, and obesity (P < .05 for all). Similar patterns were found in subgroup analyses.

Conclusion: Cost-related medication nonadherence among older adults is increasingly common, with several potentially modifiable risk factors identified. Interventions, such as medication therapy management, may be needed to reduce cost-related medication nonadherence in older adults.


Medication nonadherence is a complex behavior that can manifest in multiple forms (eg, not following administrative instructions) and conveys substantial medical and economic consequences.[1] Approximately 93.5 million Americans take at least one prescription medication, but they often do not take these drugs as prescribed, and nearly 30% of prescriptions are never filled by patients.[2,3] Medication nonadherence accounts for approximately 450 000 emergency department visits every year,[4] and 10% of hospitalizations in older adults,[5] resulting in 125 000 potentially preventable deaths each year in the United States.[6] At the individual level, each nonadherent patient requires three extra medical visits a year, adding approximately $2000 to his/her annual healthcare spending per capita.[7] Further, medication nonadherence, along with suboptimal prescribing and drug administration, results in $290 billion in avoidable medical spending annually in the United States.[8]

Older adults, aged 65 years or older, with multiple chronic conditions face medication nonadherence,[9,10] and such nonadherence is associated with potentially avoidable health services use.[8,11] For example, previous studies found that medication adherence rates among patients with at least one chronic condition can be as low as 50%,[12,13] and nearly 15% of chronically ill Americans specifically stated that costs were the main reason for medication underuse.[14,15] Furthermore, it is estimated that at least 10% of hospital admissions are related to patients' nonadherence to medications.[16,17]

Earlier studies reported that the rate of cost-related medication nonadherence among older adults was 5.4% in 2004 and dropped to 3.6% in 2006, likely representing the impact of the passage of the Medicare Modernization Act in 2003, which led to the full implementation of Medicare Part D in 2006.[15,18] Furthermore, while there are many studies reporting the prevalence of and factors associated with medication nonadherence, they are often outdated,[19–21] exclude older adults,[22,23] have limited generalizability,[21,24] or do not elicit cost-specific medication nonadherence and its reasons among older adults.[25,26]

In comparison to younger individuals, older adults have an increased risk of medication nonadherence because of multiple chronic conditions and higher medication use. Further, one of the aims of the Affordable Care Act of 2010 was to close the medication coverage gap (ie, "donut hole") of the Medicare Part D prescription drug plan.[27] While the medication coverage gap has been substantially reduced with full implementation of the Affordable Care Act in 2014,[27,28] it remains unclear if older adults still cannot adhere to prescribed medications because of costs. Thus, we addressed the following questions using a nationally representative sample: (1) What is the national prevalence of cost-related medication nonadherence among older adults? (2) Among older adults who reported cost-specific medication nonadherence, what steps did they take to address cost-related medication nonadherence? (3) What sociodemographic and health-related correlates are independently associated with cost-related medication nonadherence among older adults? (4) What sociodemographic and health-related correlates are independently associated with actions taken for such nonadherence among older adults? Are these factors different among chronically ill older adults?